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API网关授权

aws-api-gateway python-requests

shantanuo · 技术社区 · 4 年前

我使用了本教程并成功地创建了“put”端点。

https://sanderknape.com/2017/10/creating-a-serverless-api-using-aws-api-gateway-and-dynamodb/

当我遵循这个建议时,我得到了authroization required error。。

使用API网关URL。

import requests
api_url = "https://0pg2858koj.execute-api.us-east-1.amazonaws.com/tds"

PARAMS = {"name":  "test", "favorite_movie":"asdsf"}
r = requests.put(url=api_url, params=PARAMS)

回复是403

我的控制台测试是成功的,但无法从python中放入记录。

0 回复 | 直到 4 年前

jccampanero 4 年前

解决此问题的第一步是调查AWS在中返回的信息 403 回应。它将提供一个标题, x-amzn-ErrorType 以及包含具体错误信息的错误消息。你可以用 curl 在详细模式下( -v relevant documentation 获取所有可能错误原因的详细枚举。

在任何情况下,查看您的代码,很可能您没有向AWS提供必要的身份验证或授权信息。

您必须提供的信息类型取决于 which mechanism 您已配置为在API网关中访问REST API。

例如,如果您配置了 IAM based authentication ,您需要设置Python代码以生成 Authorization 带有 AWS Signature access key ID and associated secret key . AWS文件提供 an example of use with Postman .

这个 AWS documentation 还提供了几个如何使用 python requests 执行这种授权。

this example 对于向DynamoDB发布信息:

# Copyright 2010-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
#
# This file is licensed under the Apache License, Version 2.0 (the "License").
# You may not use this file except in compliance with the License. A copy of the
# License is located at
#
# http://aws.amazon.com/apache2.0/
#
# This file is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
# OF ANY KIND, either express or implied. See the License for the specific
# language governing permissions and limitations under the License.

# AWS Version 4 signing example

# DynamoDB API (CreateTable)

# See: http://docs.aws.amazon.com/general/latest/gr/sigv4_signing.html
# This version makes a POST request and passes request parameters
# in the body (payload) of the request. Auth information is passed in
# an Authorization header.
import sys, os, base64, datetime, hashlib, hmac 
import requests # pip install requests

# ************* REQUEST VALUES *************
method = 'POST'
service = 'dynamodb'
host = 'dynamodb.us-west-2.amazonaws.com'
region = 'us-west-2'
endpoint = 'https://dynamodb.us-west-2.amazonaws.com/'
# POST requests use a content type header. For DynamoDB,
# the content is JSON.
content_type = 'application/x-amz-json-1.0'
# DynamoDB requires an x-amz-target header that has this format:
#     DynamoDB_<API version>.<operationName>
amz_target = 'DynamoDB_20120810.CreateTable'

# Request parameters for CreateTable--passed in a JSON block.
request_parameters =  '{'
request_parameters +=  '"KeySchema": [{"KeyType": "HASH","AttributeName": "Id"}],'
request_parameters +=  '"TableName": "TestTable","AttributeDefinitions": [{"AttributeName": "Id","AttributeType": "S"}],'
request_parameters +=  '"ProvisionedThroughput": {"WriteCapacityUnits": 5,"ReadCapacityUnits": 5}'
request_parameters +=  '}'

# Key derivation functions. See:
# http://docs.aws.amazon.com/general/latest/gr/signature-v4-examples.html#signature-v4-examples-python
def sign(key, msg):
    return hmac.new(key, msg.encode("utf-8"), hashlib.sha256).digest()

def getSignatureKey(key, date_stamp, regionName, serviceName):
    kDate = sign(('AWS4' + key).encode('utf-8'), date_stamp)
    kRegion = sign(kDate, regionName)
    kService = sign(kRegion, serviceName)
    kSigning = sign(kService, 'aws4_request')
    return kSigning

# Read AWS access key from env. variables or configuration file. Best practice is NOT
# to embed credentials in code.
access_key = os.environ.get('AWS_ACCESS_KEY_ID')
secret_key = os.environ.get('AWS_SECRET_ACCESS_KEY')
if access_key is None or secret_key is None:
    print('No access key is available.')
    sys.exit()

# Create a date for headers and the credential string
t = datetime.datetime.utcnow()
amz_date = t.strftime('%Y%m%dT%H%M%SZ')
date_stamp = t.strftime('%Y%m%d') # Date w/o time, used in credential scope


# ************* TASK 1: CREATE A CANONICAL REQUEST *************
# http://docs.aws.amazon.com/general/latest/gr/sigv4-create-canonical-request.html

# Step 1 is to define the verb (GET, POST, etc.)--already done.

# Step 2: Create canonical URI--the part of the URI from domain to query 
# string (use '/' if no path)
canonical_uri = '/'

## Step 3: Create the canonical query string. In this example, request
# parameters are passed in the body of the request and the query string
# is blank.
canonical_querystring = ''

# Step 4: Create the canonical headers. Header names must be trimmed
# and lowercase, and sorted in code point order from low to high.
# Note that there is a trailing \n.
canonical_headers = 'content-type:' + content_type + '\n' + 'host:' + host + '\n' + 'x-amz-date:' + amz_date + '\n' + 'x-amz-target:' + amz_target + '\n'

# Step 5: Create the list of signed headers. This lists the headers
# in the canonical_headers list, delimited with ";" and in alpha order.
# Note: The request can include any headers; canonical_headers and
# signed_headers include those that you want to be included in the
# hash of the request. "Host" and "x-amz-date" are always required.
# For DynamoDB, content-type and x-amz-target are also required.
signed_headers = 'content-type;host;x-amz-date;x-amz-target'

# Step 6: Create payload hash. In this example, the payload (body of
# the request) contains the request parameters.
payload_hash = hashlib.sha256(request_parameters.encode('utf-8')).hexdigest()

# Step 7: Combine elements to create canonical request
canonical_request = method + '\n' + canonical_uri + '\n' + canonical_querystring + '\n' + canonical_headers + '\n' + signed_headers + '\n' + payload_hash


# ************* TASK 2: CREATE THE STRING TO SIGN*************
# Match the algorithm to the hashing algorithm you use, either SHA-1 or
# SHA-256 (recommended)
algorithm = 'AWS4-HMAC-SHA256'
credential_scope = date_stamp + '/' + region + '/' + service + '/' + 'aws4_request'
string_to_sign = algorithm + '\n' +  amz_date + '\n' +  credential_scope + '\n' +  hashlib.sha256(canonical_request.encode('utf-8')).hexdigest()

# ************* TASK 3: CALCULATE THE SIGNATURE *************
# Create the signing key using the function defined above.
signing_key = getSignatureKey(secret_key, date_stamp, region, service)

# Sign the string_to_sign using the signing_key
signature = hmac.new(signing_key, (string_to_sign).encode('utf-8'), hashlib.sha256).hexdigest()


# ************* TASK 4: ADD SIGNING INFORMATION TO THE REQUEST *************
# Put the signature information in a header named Authorization.
authorization_header = algorithm + ' ' + 'Credential=' + access_key + '/' + credential_scope + ', ' +  'SignedHeaders=' + signed_headers + ', ' + 'Signature=' + signature

# For DynamoDB, the request can include any headers, but MUST include "host", "x-amz-date",
# "x-amz-target", "content-type", and "Authorization". Except for the authorization
# header, the headers must be included in the canonical_headers and signed_headers values, as
# noted earlier. Order here is not significant.
# # Python note: The 'host' header is added automatically by the Python 'requests' library.
headers = {'Content-Type':content_type,
           'X-Amz-Date':amz_date,
           'X-Amz-Target':amz_target,
           'Authorization':authorization_header}


# ************* SEND THE REQUEST *************
print('\nBEGIN REQUEST++++++++++++++++++++++++++++++++++++')
print('Request URL = ' + endpoint)

r = requests.post(endpoint, data=request_parameters, headers=headers)

print('\nRESPONSE++++++++++++++++++++++++++++++++++++')
print('Response code: %d\n' % r.status_code)
print(r.text)

我认为它很容易适应你的需要。

在控制台中,一切正常,因为当您在API网关中调用REST端点时,您将连接到一个已通过身份验证并有权访问这些REST端点的用户。